Massive digitalis toxicity and hyperkalemia./nClinical background: A suicidal patient has taken a l

Fråga: Massive digitalis toxicity and hyperkalemia.

Clinical background: A suicidal patient has taken a large number of digoxin tablets. A potassium value of 10 mmol/l was discovered. Kidney function and other laboratory values were normal. The patient has not taken any supplemental potassium tablets. Is there any possibility that the digitalis toxicity could have caused the hyperkalemia?

Sammanfattning: Hyperkalemia at levels of up to 8.7 mmol/l has been reported after massive digoxin intoxication. A potassium value of 10 mmol/l should not be inconceivable in a patient with massive overdose of digoxin. In this specific case the very high potassium value probably could be caused by the digitalis toxicity.

Svar: Serum potassium elevation from 5.7-8.7 mmol/l was present in 11 of 26 cases of advanced intoxication (1,2). Presumably, this elevation resulted from inhibition of sodium potassium - ATPase and thus the sodium and potassium transport throughout the body. All 26 patients had advanced cardiac rhythm disturbances. After treatment with Fab fragments, all hyperkalemia cases recovered.

In one case report (3) a 78-year-old male ingested 7.5 mg digoxin. On arrival to hospital, 24 hours later, hyperkalemia (6.1 mmol/l) was detected that was normalized after two days. The digoxin concentration in plasma on the first day was 18.4 nmol/l. During the first days of intoxication, atrial arrhythmias and AV-block predominated. No ventricular arrhythmias were seen.

Personal communication with Dr Jogestrand at the Department of Clinical Physiology (4) could not exclude a possible relationship between such high levels of potassium as in the present case of massive intoxication with digoxin. 1 Smith TW: Digitalis toxicity: clinical management of advanced life-threatening toxicity resistant to conventional therapy. In: Digitalis glycosides (Ed by Sonnenblick EH, Lesch M). Grune & Stratton, Inc. 1986; page 311-319 2 Smith TW, Butler VP Jr, Haber E, Fozzard H, Marcus FI, Bremner WF, Schulman IC, Phillips A: Treatment of life-threatening digitalis intoxication with digoxin-specific Fab antibody fragments. N Engl J Med 1982; 307: 1357-1362 3 Bertler Å, Gustafson A, Redfors A: Massive digoxin intoxication. Acta Med Scand 1973; 194: 245-249 4 Personal communication, Dr Tomas Jogestrand, Department of Clinical Physiology, Huddinge Hospital